Defensive publication

ABSTRACT

THE METHOD OF PRODUCING A GELLED HYDROXYLATED POLYMER FOAM, SUCH AS POLYVINYL ALCOHOL FOAM, WHICH WILL ADHERE TO VERTICAL AND OVERHEAD STRUCTURES WHICH COMPRISES PREPARING AN AQUEOUS SOLUTION CONTAINING 1 TO 15 PERCENT BY WEIGHT OF HYDROXYLATED POLYMER AND 0.1 TO 1.5 PERCENT BY WEIGHT OF A WATER-SOLUBLE GELLING AGENT PRECURSOR, SUCH AS POTASSIUM TITANIUM OXALATE OR FERRIC CHLORIDE, AND HAVING A PH OR NOT MORE THAN 5, MIXING SAID SOLUTION WITH AIR IN A FOAM GENERATOR THEREBY FOAMING SAID MIXTURE, AND CONTACTING THE RESULTING FORM, AT A POINT ADJACENT TO THE POINT AT WHICH THE FOAM ISSUES FROM THE FOAM GENERATOR, WITH AN ALKALINE PH MODIFYING AGENT, SUCH AS AMMONIA OR AMMOMIUM HYDROXIDE, FOR EXAMPLE BY INJECTING AMMONIA INTO THE FOAM, IN AN AMOUNT SUFFICIENT TO INCREASE THE PH OF THE FOAM TO AT LEAST 7, WHEREBY SAID FOAM BECOMES TACKY WITHIN 2 SECONDS AFTER CONTACT WITH SAID ALKALINE AGENT AND SAID FOAM GELS.

DEFENSE/E PULlCATlON UNITED STATES PATENT OFFICE Published at therequest of the applicant or owner in accordance with the Notice of Dec.16, 1969, 869 0.G. 687. The abstracts of Defensive Publicationapplications are identified by distinctly numbered series and arearranged chronologically. The heading of each abstract indicates thenumber of pages of specification, including claims and sheets ofdrawings contained in the application as originally filed. The files ofthese applications are available to the public-for inspection andreproduction may he purchased for 30 cents a sheet.

Defensive Publication applications have notibeen examined as to themerits of alleged invention. The Patent Oflice makes no assertion as tothe novelty of the disclosed subject matter.

PUBLISHED AUGUST 8, 1972 T901 022 PROCESS FOR FOAMlltNG AND GELLINGHYDROXYLATED POLYMERIC MATERIAL Bernard C. Lawes, Wilmington, DeL,assignor to E. l. du

Pont de Nemours and Company, Wilmington, Del. Continuation ofapplication Ser. No. 846,619, July 31,

1969, which is a continuation of application Ser. No.

509,620, Nov. 24, 1965. This application Aug. 16,

1971, Ser. No. 172,275

Int. Cl. (308i 29/26, 47/08 US. Cl. 260-2.5 L No Drawing. 16 PagesSpecification The method of producing a gelled hydroxylated polymerfoam, such as polyvinyl alcohol foam, which will adhere to vertical andoverhead structures which comprises preparing an aqueous solutioncontaining 1 to 15 percent by weight of hydroxylated polymer and 0.1 to1.5 percent by weight of a water-soluble gelling agent precursor, suchas potassium titanium oxalate or ferric chloride, and having a pH of notmore than 5, mixing said solution with air in a foam generator therebyfoaming said mixture, and contacting the resulting foam, at a pointadjacent to the point at which the foam issues from the foam generator,with an alkaline pH modifying agent, such as ammonia or ammoniumhydroxide, for example by injecting ammonia into the foam, in an amountsufiicient to increase the pI-I of the foam to at least 7, Whereby saidfoam becomes tacky within 2 seconds after contact with said alkalineagent and said foam gels.

